Ruminant Nutrition Flashcards
how many animals are ruminants worldwide?
2.8 billion
how many ruminants are cattle and sheep?
2.2 billion
list the major domesticated ruminant species
cattle
sheep
goat
buffalo
reindeer
yak
what are the three feeding types for ruminant classification?
concentrate selectors (soluble fiber, berries, fruit)
intermediate selectors (more fiber components, adaptable to both concentrate and low quality feed)
grass/roughage feeders (most advanced to foregut utilization)
define pseudoruminant
cud chewing animal that has 3 compartment stomach and has feet that resemble pads not hooves
describe the three compartment stomach of pseudoruminants
first two = resemble reticulum and rumen in terms of size and function. **secretes mucus and buffer (unlike ruminant*
third part = glandular tissue similar to abomasum
which species are examples of pseudoruminants?
camel, llama
do ruminants prefer sweet or sour taste?
sweet
ruminant feed costs represent ___% of total production
45-60%
what’s the key for ruminant digestive physio?
OPPORTUNITY
since diet can be so diverse
REWATCH TO SEE IF WE NEED TO KNOW
SLIDE 17
concentrate selectors must handle a ___ range of plant toxins and/or defense factors (tannin)
wider range
describe microbial masses in concentrate selectors
LOW/NO protozoal activity
HIGH amylase activity
why is feed intake so important?
determines production level
affects rate of passage and digestion in rumen
determines microbial protein synthesis in rumen
important for formulating nutrient concentration in diet
describe the chemical traits of feeds related to intake
energy concentration (metabolizable vs net)
fiber content (NDF, lignin)
nutrient content (N, S, salt)
describe the physical traits of feed related to intake
moisture
particle size
density
list some physiological states that affect intake of food
lactation (increase)
pregnancy (decrease in last trimester)
temperature stress (heat decreases, cold increases)
BCS
hormones (leptin, ghrelin)
what are the four main theories of feed intake regulation in ruminants?
physical constraints - capacity of GI tract
metabolic constraints - energy demands
efficiency of oxygen use
water content of feed
why is anabolic processing so critical in the rumen?
supply protein
meet vitamin B requirements of host
what are some consequences to fermentation?
pre-gastric hydrolysis
conversion to microbial biomass (VFA, CO2, methane, ammonia)
what are some advantages to pregastric fermentation?
provide energy from fibrous material
microbes provide AA and B vitamins
reduces amount of undigested product
what are some disadvantages of pregastric fermentation?
digests readily available substrates (starch, sugar, protein) LESS EFFICIENTLY than in SI
reduces quality of proteins
fermentation in the rumen mostly involves breakdown of ___
sugars
are AA absorbed from the rumen?
NO
amino acids and small peptides are transported into ___ cells in the rumen and is used for synthesis of ___ proteins
bacterial
synthesize microbial proteins
which proteins are NOT degraded in the rumen?
BYPASS PROTEINS
natural (corn, blood proteins, feather meal)
modification of feed proteins to make them less degradable (via heat or chemical)
how is fat digestibility influenced in the rumen?
DM intake
amount of fat consumed (decreases with increased intake)
degree of saturation (decreases with increased sat)
describe the lipid content of forages
LOW fat content (1-4% of DM)
high linolenic acid proportion
diglycerides in fats of leaves
describe the lipid content of grains
VARIABLE content (4-20% DM)
high linolenic acid proportion
triglycerides in oils of seeds
describe hydrogenation of fatty acids in rumen
what depresses hydrogenation of FA
linoleic acid
how does fat effect ruminant fermentation and food intake?
reduced intake
reduced fiber digestion
reduced milk fat
increased propionate:acetate
which fat is MORE inhibitory to rumen fermentation…polyunsaturated or saturated?
polyunsat
ruminant feeds normally contain ___ levels of fats/oils
LOW
2-4%
what are some reasons to add fat to a diet?
increase energy density
help increase milk production or gain
improve diet and pellet characteristics
lubricate feed processing equipment
what are protected fats that are fed to ruminants?
Ca salts of FA, hydrogenated fats
ones that have little/no effect on fiber digestion
sold in dry form
easy to mix
expensive fat source
what are unprotected fats?
animal fats
plant oils - unsaturated FA depress fiber digestion
dairy calves should receive ___% BW of colostrum within first 24 hours of life, with at least half of that being within first ___ hours of life
10%
half within 3 hours
dairy calves should receive ___% BW of cow milk or ___% milk replacer per day
10% milk
10-13% milk replacer
when do you start feeding dairy calves grain aka calf starter?
first/second week of life
calves are weaned when they eat ___ lbs of calf starter per day
0.5-1 lb
offer alfalfa to calves starting at week __
2
what happens if you overfeed calf with powdered milk?
abomastitis
far off dry dairy cows (60-30d) are fed ___ fiber and ___ energy diet
high fiber
moderate energy
list some common nutrients for far off dry dairy cows
corn silage
alfalfa
soybean meal
soyplus
wheat straw
grass/oat hay
up close dry dairy cows (30-0d) are fed ___ energy, ad libitum ___
moderate energy
TMR
list some common nutrients for close up dry dairy cattle
cereals
hay
low K hay
wheat middlings
brewer grain
corn silage
what do you feed lactating and feedlot animals?
TMR
bypass protein should be what percent of protein content of high producing cows (lactating)?
40-50%
do NOT exceed __ lbs of grain daily
40
what’s the rule of thumb for beef cows protein requirements during breeding?
7-9-11
what’s meant by the 7-9-11 rule for beef cows?
proteins requirements are 7, 9, 11% in mid gestation, late pregnancy, and lactation
what is the rule of thumb for protein in feeder beef cows?
14-12-10
what’s the 14-12-10 rule for beef?
protein requirement for feeder calves is
14% in 550-800 lbs
12% in 800-1000 lbs
10% in 1000 lbs to finish
what’s the rule of thumb for energy requirement in beef cattle gestation?
55-60-65
what’s the 55-60-65 rule for beef cattle?
energy requirement in %TDN
mid gestation is 55%
late gestation is 60%
early pp is 65%
the TMR for feedlot cattle is ___% concentrates and ___% fiber
80-90% concentrate
10-20% fiber
what percent of BW should feedlot cattle eat per day in DM?
1.5-3.5%
how many lbs should feedlot cattle gain per day?
2.5-3.5 lbs
how can implants help with feedlot cattle?
partitions energy to muscle and fat
increases IGF1
increase ADG
what does the ionophore, lasalocid do to beef cattle?
increase feed efficiency
prevent bloat
prevent rumen acidosis
how can ruminants get pulmonary edema from diet?
switch from dry forage to lush green pasture
main symptom is labored breathing
tryptophan
how does tryptophan in diet cause pulmonary edema?
since tryptophan undergoes decarboxylation and deamination in rumen…producing 3-methyl indole (TOXIC)
controlling ___ in diet helps reduce risk of pulmonary edema
ionophores
what are the main types of bloat?
free gas bloat
frothy (legume, grain) bloat
pasture bloat
what is gas bloat?
gas trapped in rumen, forms foam
eructation is inhibited
esophageal obstruction may be causing bloat
what’s one way to differentiate free gas from frothy bloat?
passing stomach tube
what is frothy bloat?
some free gas present
whole rumen filled with froth/foam
what are the two subtypes of frothy bloat?
legume
grain
what is legume bloat?
depends on rate of fermentation
ALFALFA
frothy
how do you treat pasture bloat?
rumenotomy/cannula
stomach tube
fistula if chronic
what is ruminal lactic acidosis?
excessive highly fermentable CHO is main cause
rapid lactic acid production
lactic acidosis is the number one ___ problem
feedlot
lactic acidosis causes rumen osmotic P to ___, and __ pH
increase
decreases pH
what is ketosis?
negative energy balance caused by prolactin and growth hormone that establishes high rate of milk production
causes FA burden that is converted ro ketones in liver
what is polioencephalomalacia (PEM)?
lesions of brain tissue
brain swelling
symptoms - dullness, spasms, arched back, convulsion, coma
what causes PEM?
severe thiamin deficiency
what is thiamin?
normally made by rumen bacteria
what is hypocalcemia?
low Ca after birth
since Ca is drained into milk/colostrum
unable to mobilize Ca from bone
